1. Field of the Invention
This invention relates generally to closures for containers of the type having a sifter disk secured in place at the lip of the container and as typically employed for dispensing small or controlled amounts of various spices by means of a shaking motion imparted to the container while it is inverted.
2. Description of the Related Art Including Information Disclosed Under 37 CFR .sctn..sctn.1.97-1.99
The following U.S. patents are hereby cited as being of interest in the field to which this invention pertains.
______________________________________ U.S. Pat. Nos.: ______________________________________ 2,614,734 2,645,382 2,729,363 3,031,107 3,512,681 4,498,608 4,961,521 5,086,952 ______________________________________
In addition, the following references are cited as a consequence of their having been made of record during the prosecution of applicants' co-pending application Ser. No. 08/018,232 identified above:
______________________________________ U.S. Pat. Nos.: 2,576,416 3,276,642 3,388,841 5,183,171 4,066,181 British Patent No. 1,024,178 ______________________________________
In U.S. Pat. No. 4,498,608, FIGS. 1 and 2 disclose a dispenser for condiments, comprising a container having a perforated "sifter" disk which is retained by pressing it in place on the container lip, in combination with a second disk which is perforated and which is adapted to be snapped into the closure for the container, and which together with the closure forms a chamber in which absorbent material is placed. In use the second disk remains with the closure, whereas the first disk remains with the container. Grains of rice in the chamber function to absorb undesirable moisture from the condiment during storage, for example.
U.S. Pat. No. 2,645,382 discloses a dispenser having a container and a sifter disk clamped between two rings (20, 22) and against the lip of the container, by means of a removable threaded sleeve (10). The sleeve is applied to the container after the closure (presumably not shown) has been removed. The sleeve and sifter disk are removed at such time as the closure is to be reapplied, as presently understood.
U.S. Pat. No. 4,961,521 discloses a combination storage and metering dispenser employing a variable-volume metering chamber having a sifter disk at one end, and a removable snap-on closure member or cap (22) covering the sifter disk. A predetermined quantity of granular or other material is first discharged into the metering chamber (29), after which the measured quantity can be discharged through openings (30) in a perforated end cap or member (19) of the chamber.
U.S. Pat. No. 3,512,681 illustrates another type of metering dispenser for particulate material, employing a storage canister (4) and a removable transparent container (16) which functions as a metering container. The latter has measuring indicia on its side wall, and a perforated end, FIG. 2. A closure cap (24) is receivable on the end. Dispensing is accomplished by first filling the metering container with the desired amount of material, and thereafter shutting off communication between this chamber and the canister. The metered quantity of material is then discharged through the perforated end of the metering chamber.
U.S. Pat. Nos. 2,614,734; 3,031,107; and 2,729,363 illustrate various forms of containers having either perforated members or gratings of a configuration which is intended to pulverize or disintegrate lumps which may form in the product being discharged, and thereby minimize the tendency for clogging. Nos. '734 and '107 utilize gratings that have knife-like edges which are intended to come into contact with the product and thus break it up into small pieces. No. '363 discloses two embodiments, one employing a spiral spring to effect the break-up, and a second employing a grating constituted of a flat disk with elongated openings or slits, which allegedly pulverize the product during shaking of the container, so as to eliminate clogging due to lumps.
U.S. Pat. No. 5,086,952 illustrates and describes a dispenser having a perforated lid which is pressed into the mouth of a container, and tightly seated therein. A separate, removable cover (30) in the form of a screw cap seals the container for storage.
The various devices disclosed in the above identified patents do not appear to have enjoyed any significant success in the marketplace. One reason may have been the relative complexity of the various structures, and the necessity for special operations on the part of the consumer in order to properly operate and use the particular dispensers in their intended manners. Also, with separate sifter and closure components, there existed the possibility of the sifter/measuring parts becoming either lost or misplaced when the dispenser was not being used.
Finally, the problem of assembly of these dispensers in a cost-effective manner is not addressed in the prior art noted above.
In order to be competitive today, it has been customary to employ automated procedures for both the filling of dispensers, and the resultant capping thereof. Automated capping equipment is well known in the dispenser field. Prior designs which did not lend themselves to use with such equipment were not feasible from the standpoint of economy in manufacture and assembly, and thus were not suitable for adaptation to present day commercial use and sale.
In prior containers employing both a sifter member and a closure, where automated equipment was employed the procedures that were conventionally followed were to first fill the dispenser with the desired quantity of material (usually granular in nature, i.e. spices and the like), after which a sifter disk was installed over or onto the opening of the container. Following this, a screw cap closure could be applied.
One of the problems with this procedure was that it consisted of two separate operations, both involving filled containers. During such operations, extreme care had to be exercised in insuring that the placement of the sifter disk was correct and did not result in breakage (possibly leading to malfunction of the dispenser at the time the consumer first used it, and worse, possible introduction into the container of fragments of plastic/glass resulting from shearing of either the disk or container.)
After the sifter disk was assembled to the container, there thus arose a need for an intermediate inspection step of some type, performed either visually by an operator, or by means of an automatic sensor, adapted to determine proper seating of the disk, prior to application of the closure.
Assuming that the disk was assembled in its intended manner and without breakage, the screw caps constituting the closures could then be applied in a second step, again usually employing automatic capping equipment.
With the procedure set forth in the immediately preceding paragraphs, there sometimes arose problems in achieving proper seating of the disk and/or closure cap. For example, if the disk were to be improperly seated, successful application of the closure cap could not be carried out.